Insole assembly

ABSTRACT

An insole assembly is provided comprising an insole having an upper surface upon which an underside of a foot may contact and be supported. The insole assembly has at least one protrusion which projects away from the upper surface of the insole. At least one of the protrusions is detachably connected to the insole. The protrusions may be interchanged to customize an insole assembly to provide enhanced cutaneous stimulation of targeted regions of a foot.

BACKGROUND Technical Field

The present disclosure relates to an insole assembly for an item of footwear.

Description of the Related Art

Falling and unsteadiness of gait are common problems for many older people and those with peripheral nervous system disorders, such as diabetic neuropathy. It is generally accepted that the age-related deterioration of the somatosensory and neuromuscular systems is closely related to increased postural sway, poor balance control and ultimately higher risks of falling. Due to degenerative changes and foot deformities, older people and sufferers of neuromuscular system disorders typically wear slippers made of excessively soft materials and/or oversized footwear at home that can comfortably accommodate painful feet and foot deformities. Inappropriate footwear has been identified to contribute to up to 45% of falls, whilst walking barefoot or in socks also increases the risks of falls.

Recently, footwear that offers acupressure massage has been popular among the elderly and infirm. Shoe manufacturers claim that massaging units in the insoles can apply pressure onto acupressure points on the sole of the feet and allegedly improve blood circulation. However, the effects and selection of fabrication materials that improve sensory functions, maintain dynamic stability with postural variables and the anticipated pressure distribution on the plantar surface are not known. The raised texture and acupressure knobs inevitably impose significant challenges on the distribution of the plantar pressure as a result of reductions in the surface contact area.

On the other hand, the use of soft cushioning foam materials in the construction of the footwear midsole is widely accepted as a means of enhancing the level of comfort of shoes, and as such, commonly recommended as a beneficial feature in footwear for older people. In reality, the use of soft and thick materials in footwear midsoles leads to instability. The midsole material induces a state of sensory insulation, thereby reducing afferent inputs to the brain with regard to foot position.

Attempts have been made to improve footwear. U.S. Pat. No. 5,664,342A and U.S. Pat. No. 4,694,831A disclose massaging knobs/bumps arranged in special areas of the insole in accordance with the key meridians and organ locations and/or reflex zones to activate certain organs. U.S. Pat. No. 5,682,690A discloses massage footwear which includes raised rods supported by an adjustable spring to deliver a massaging force onto the plantar of the foot. US 20120167414A1, 8051582B2, U.S. Pat. No. 7,243,446B2, and U.S. Pat. No. 6,237,256B1 each suggest that cutaneous sensation from the perimeter and/or specific regions of the plantar foot surface can be increased by using protrusions and/or textures as interventions on lower extremity movement and keeping the body's center of gravity balanced.

It is an object of the present disclosure to provide an alternative and/or improved insole assembly that enhances stimulation and tactile sensitivity of the sole of a foot.

BRIEF SUMMARY

In accordance with a first aspect of the present invention, there is provided an insole assembly comprising an insole having an upper surface for supporting and contacting an underside of a foot, and at least one protrusion projecting away from the upper surface, wherein at least one protrusion is detachably connected to the insole.

Advantageously, by providing one or more protrusions detachably connected to the insole, a customized insole assembly may be assembled with one or more projecting parts that extend from the surface of the insole at specific locations to provide stimulation to corresponding parts of the foot of a wearer. Since the one or more protrusions are detachably connected to the insole, different protrusions with different properties such as size or rigidity may be interchanged according to the wearer's requirements. By customizing an insole assembly with one or more protrusions, different levels of stimulation of plantar sensation and support to the foot of a wearer may be provided at specific locations to guide the wearer when walking and to improve the wearer's balance. In addition, an insole assembly according to the present disclosure can be incorporated into different footwear items and can therefore be used to convert ordinary footwear items into footwear items that provide enhanced stimulation and support to a wearer's foot.

The one or more protrusions may comprise a projecting part which projects from the surface and a connecting part which extends away from the projecting part and into the insole. The projecting part of one or more protrusions may comprise a first part and a second part and wherein the first part has a different rigidity from the second part. The second part may at least partially surround the first part. The second part may be less rigid than the first part.

One or more protrusions may comprise a compressible material. One or more protrusions may comprise an elastomeric material. One or more protrusions may comprise silicone material. One or more protrusions may be detachably connected to the insole by a friction fit. One or more protrusions may be detachably connected to the insole by a threaded connection.

The insole assembly may comprise more than one protrusion and two or more protrusions may be different sizes. The insole assembly may comprise more than one protrusion and two or more protrusions may be different shapes. The insole assembly may comprise more than one protrusion and the connecting part of two or more protrusions may be substantially the same.

The insole assembly may comprise a first layer and a second layer, the first layer may comprise the surface upon which an underside of a foot may be supported and the one or more protrusions may be detachably connected to the second layer and extend through the first layer. The first layer may comprise one or more apertures and one or more protrusions may extend through a corresponding aperture.

The insole assembly may further comprise an arch support arranged between the first layer and the second layer. The arch support may be made from composite material.

One or more protrusions may be arranged to project from the surface at or around a heel contacting portion of the surface. One or more protrusions may be arranged to project from the surface at or around a metatarsal head contacting portion of the surface.

The insole assembly may further comprise a shock absorbing material at or around a heel contacting portion of the surface. The insole assembly may further comprise a shock absorbing material at or around a metatarsal head contacting portion of the surface.

At least part of one or more protrusions may be frusto-conical in shape.

According to a second aspect of the present invention, there is provided a sole member comprising an insole assembly according to the first aspect, a midsole and an outsole.

According to a third aspect of the present invention, there is provided a footwear item comprising an insole assembly according to the first aspect.

According to a fourth aspect of the present invention, there is provided a method of assembling an insole assembly comprising:

providing an insole,

selecting one or more protrusions from a group of protrusions of different sizes, and

attaching the selected one or more protrusions to the insole.

The method may further comprise the steps of:

selecting an arch support from a group of arch supports of different rigidities, and

incorporating the selected arch support into the insole.

According to a fifth aspect of the present invention, there is provided a kit for assembling an insole assembly comprising an insole having an upper surface for supporting and contacting an underside of a foot, the insole having at least one connecting part for receiving a protrusion, and a plurality of protrusions connectable to respective connecting parts of the insole such that at least one protrusion projects away from the upper surface.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

Preferred embodiments of the present disclosure will be explained in further detail below by way of examples and with reference to the accompanying drawings, in which:

FIG. 1 shows an exploded view of a sole of footwear comprising an insole assembly according to the present invention;

FIG. 2 shows four different parts of an insole assembly shown in FIG. 1; and

FIG. 3 shows an insole part of the insole assembly shown in FIG. 1.

DETAILED DESCRIPTION

Referring to the drawings, there is a shown a sole member 1 comprising an insole assembly 13, a midsole 9 and an outsole 11. In the embodiment depicted, the sole member 1 is intended to be incorporated into indoor geriatric footwear (not shown). It will be appreciated that the sole member 1 need not be limited specifically to use in geriatric footwear and could be used in any footwear in which stimulation of the cutaneous sensation is desired such as outdoor sandals.

The insole assembly 13 comprises an insole top 3, an arch support 5, an insole bottom 7 and a plurality of resilient protrusions or nodules 19. The insole top 3 and insole bottom 7 are each made from a cushioning material such as low density vinyl acetate or soft polyurethane. The shape of the perimeter of the insole top 3 and insole bottom 7 are substantially identical such that when the insole top 3 overlays the insole bottom 7, they together form an insole 14 suitable for use with an item of footwear and for providing a supporting surface for the sole of a foot. The insole top 3 and insole bottom 7 are at least partially separable so that the arch support 5 can be inserted therebetween at or around the arch area and toward the heel end of the insole 14. In the embodiment depicted, the insole 14 is provided in a thickness of approximately 10 mm but other suitable thicknesses may be chosen as will be apparent to a person of ordinary skill in the art.

The insole top 3 further comprises a shock absorption material such as polyurethane arranged at or around the heel area 15 and the metatarsal heads area 17 of the insole 14, respectively. The shock absorption material is provided and strategically positioned to absorb impact forces to the foot during heel strike and foot propulsion.

The nodules 19 comprise a projecting part 21 and a connecting part 23 which is attached to and extends away from the underside of the projecting part 21. In the embodiment depicted, the projecting part 21 of each nodule 19 is substantially frusto-conical in shape with a substantially flat upper surface which is intended, in use, to come into interfacial contact with the sole of a foot. Other suitable shapes will be apparent to a person of ordinary skill in the art. For example, the projecting part 21 of one or more nodules 19 could be hemi-spherical, cylindrical, cuboidal or conical as desired. The projecting part 21 is oriented such that the upper surface of the projecting part 21 has a smaller diameter than the lower surface. The projecting part 21 is intended, in use, to contact and stimulate the underside of a foot.

The projecting part 21 comprises a core 25 and an outer sheath 27 which substantially surrounds and encapsulates the core 25. In the embodiment depicted, both the core 25 and the sheath 27 are made from silicone material which gives the projecting part 21 a degree of compressibility. Other suitable materials may be used as will be apparent to a person of ordinary skill in the art such as elastomeric materials. The core 25 of the projecting part 21 is made from a silicone material which has a greater rigidity than the sheath 27 so as to provide a degree of cushioning for the sole of a foot and to avoid overly aggressive stimulation. With reference to FIG. 2, in the embodiment depicted, the nodules 19 are provided in three different sizes whereby the projecting parts 21 each have lower surface diameter of approximately 10 mm 19 a, 14 mm 19 b or 20 mm 19 c and a height of approximately 10 mm.

It is envisaged that, nodules 19 of different hardness could be used to adjust the level of stimulation. For example, one or more nodules 19 with a shore hardness of 8 on the Shore A scale could be used. One or more nodules 19 having a different shore hardness could be used according to patient stimulation requirements.

The connecting part 23 of each nodule 19 is substantially the same shape and size and comprises a disc shaped body and a male stud 29 which is approximately 5 mm in height and diameter and which is intended, in use, to mate with a female recess. In the embodiment depicted, the connecting part 23 forms one half of a snap fastener. The connecting part 23 is adhered to the lower surface of the projecting part 25 such that the male stud 29 extends away from the lower surface of the projecting part 25. The connecting part 23 may be made from any suitable material as will be apparent to a person skilled in the art such as metal or plastic.

The insole bottom 7 comprises a plurality of female sockets or rings 31 for receiving a male stud 29 of each nodule 19. The female sockets 31 comprise the second part of the snap fastener connection. The female sockets 31 are oriented such that the opening of each socket 31 is directed upwardly from a surface of the insole bottom 7 so as to receive the male stud 29 of a nodule 19 from the upper surface of the insole top 3. The female sockets 31 are spaced apart from one another such that the distance between the respective centers of two adjacent female sockets 31 is at least approximately 20 mm. Thus, sufficient space is provided between two adjacent female sockets 31 such that the largest 20 mm nodules 19 c can be connected to adjacent female sockets 31 respectively.

The insole top 3 comprises a corresponding number of substantially circular apertures 33. The apertures 33 are positioned on the insole top 3 such that when the insole top 3 is interfaced with the insole bottom 7, the apertures 33 are substantially aligned with the female sockets 31. Thus, the female sockets 31 may be accessed through the insole top 3 via the apertures 33. Whilst a snap fastener is the connection means in the embodiment depicted, it will be apparent to a person of ordinary skill in the art that other appropriate fastening means may be used such as hook and loop, screw fitting, bayonet fitting or magnetic connection.

The diameter of the respective apertures 33 is chosen to be less than the diameter of the lower surface of the projecting part 21 but greater than the shaped body of the connecting part 23. Thus, the footprint of the projecting part 21 of each nodule 19 is greater than the aperture 33 so that the lower surface of the projecting part 21 abuts the upper surface of the insole top 3 and the connecting part 23 extends into the insole 14 through the apertures 33 to interface with a corresponding female socket 31.

The female sockets 31 and, hence, apertures 33 are strategically positioned on the insole 14 such that nodules 19 connected to the female sockets 31 will contact regions of the sole of a foot that are considered to provide stimulation of the cutaneous sensation. In the embodiment depicted, five female sockets 31 are positioned across the width of the insole 14 at a region of the insole 14 which, in use, contacts the region of the foot that comprises the join between the metatarsals and the phalanges. Thus, when five nodules 19 of desired size are connected to corresponding female sockets 31, each of the five nodules 19 contacts a corresponding join between the metatarsal and phalange of a foot. A further four female sockets 31 are located at a region of the insole 14 which, in use, contacts the lateral calcaneus region of the foot.

Thus, when nodules 19 of desired sizes are attached to the insole 14 at the predetermined strategic locations, an insole assembly 13 capable of providing stimulation of cutaneous sensation at specific regions of the sole of a foot is created. The strategic positioning of the female sockets 31 on the insole 14 and the different sized nodules 19 provides a number of different possible combinations for creating a customized insole assembly according to a wearer's needs.

The arch support 5 provides an extra level of customization to the insole assembly 13. In the embodiment depicted, the arch support 5 is made from a carbon fiber composite which is sufficiently flexible to be fabricated into different shapes and structures as desired. The arch support 5 comprises a raised portion 35 to provide support for the arch region of a foot. The raised portion 35 comprises a cushioning material 36 made from low density ethylene vinyl acetate (LDEVA) or soft polyurethane for added comfort.

The arch support 5 comprises a plurality of apertures 38 at least equal in number to the female sockets 31 arranged at the heel end of the insole 14. The apertures 38 of the arch support 5 are positioned such that, when the arch support 5 is incorporated into the insole 14 such that the arch support 5 is sandwiched between the insole top 3 and insole bottom 7, the apertures 38 are substantially aligned with corresponding female sockets 31 and insole top apertures 35 at the heel end of the insole 14. Thus, one or more nodules 19 can be inserted into the female sockets 31 of the insole 14 even when the arch support is incorporated into the insole assembly 13.

In the embodiment depicted, three separate arch supports 5 are provided each having a different stiffness and/or bending rigidity. The stiffness may be a measure of the resistance of the arch support 5 to bending and the bending rigidity may relate to the ability of the arch support 5 to return to its original shape following deformation. It is believed that arch supports with good bending rigidity improve the downwardly applied forces by the foot and encourage even energy expenditure during walking.

The three arch supports 5 are provided in three degrees of stiffness and/or bending rigidity, namely, low, medium and high stiffness and/or rigidity. The degree of stiffness and/or bending rigidity is at least partly dictated by the number and/or thickness of layers of material used to form the composite material and the type of material chosen to fabricate the arch support 5. For example, an arch support 5 comprising a composite material with more layers will have a higher stiffness than an arch support with less layers.

In addition to supporting the arch of a foot, the arch support 5 also performs the function of a shank and serves to retain the shape of an item of footwear in which the insole 14 is inserted and/or to enhance the flexibility of the footwear. Since the arch support 5 is made from composite material, it has a high strength to weight ratio. The choice of arch support 5 in terms of stiffness and/or bending rigidity is partly dependent on the plantar geometry of the foot of a wearer and the sensory quality of the wearer's skin. For example, an individual with a low cutaneous sensation may require an arch support 5 with a higher rigidity so as to increase the sensitizing effect of the insole assembly 13.

The midsole 9 comprises a relatively thick protective, shock absorbing layer made from a suitable material such as ethylene-vinyl acetate (EVA) or PPT. The midsole provides stability to an item of footwear and forms a base upon which the insole assembly 13 may be supported. The midsole 9 comprises a three dimensional contoured upper surface having a raised arch region which includes a cushioning material such as soft polyurethane for enhanced comfort. The midsole 9 is tapered from the heel to the toe such that it is thicker at the heel and progressively thinner toward the toe.

A hard wearing outsole 11 having substantially the same outline shape as that of the midsole 9 and insole 14 is adhered to the underside of the midsole 9 to provide a layer to protect the midsole 9 and insole 14 from damage from the external environment and the ingress of moisture. The insole assembly 13, midsole 9 and outsole 11 together form the base of an item of footwear for supporting a foot of a wearer on a surface. The insole assembly 13 is arranged to rest on the upper surface of the midsole 9 and is removable so that other insoles may be used with the footwear.

In use, a wearer of footwear desiring enhanced comfort, support and stimulation of the cutaneous sensation of the feet may assemble an insole assembly 13 tailored to the wearer's requirements. Depending upon the arch profile of the wearer and level of cutaneous sensation of the soles of the feet, different arch supports 5 and nodules 19 may be used accordingly. For example, where enhanced stimulation of the cutaneous sensation of the metatarsal heads region of the feet is required, one or more 20 mm nodules 19 c may be attached to corresponding female sockets 31 of the insole 14.

Alternatively, it might be that the medial metatarsal heads of the wearer's foot require less cutaneous sensation than the lateral metatarsal heads. In this case, the wearer may conveniently detach two of the largest nodules 19 c from the medial side of the insole 14 and replace them with two smaller nodules 19 a, 19 b such as, for example, the 14 mm nodules 19 b. The use of the snap fastener connection between the nodules 19 and the insole 14 enables the wearer to quickly and easily change nodules according to desired requirements.

In addition to the nodules 19, a wearer may also benefit from the use of an arch support 5 to provide extra support, comfort and/or improved motion control. Depending on the wearer's level of desired plantar sensation stimulation, state of the wearer's arches and posture, a suitable arch support 5 may be inserted between the insole top 3 and insole bottom 7. By interchanging between the different arch supports 5, a wearer may find an insole assembly setting that is acceptable and that increases the wearer's plantar sensation stimulation and improves balance.

Where it is desired to have a flat smooth insole assembly without projecting nodules 19, the nodules 19 can be easily removed and replaced with inserts 40 that have no projecting part 21 and that comprise a substantially flat piece of material 42 made from elastomeric and/or EVA material and which is arranged such that, when the replacement stud is inserted into a corresponding female socket 31, the flat piece of material 42 is substantially flush with the upper surface of the insole 14.

An insole assembly 13 can be constructed with nodules 19 that causes indentations in the sole of a foot at strategic locations according to the unique needs and sensory conditions of an individual's feet. A customized insole assembly 13 according to the disclosure can be used to increase a wearer's control over body balance with adequate foot-insole interfacial pressure.

Different sized nodules 19 can be strategically placed at different plantar locations in different orientations to vary the stimulation effect. The changeable arch support 5 serves as a stabilization device to enhance foot support due to the flattening of the longitudinal arch in the elderly and individuals with flat feet. The use of an arch support 5 can increase the contact area of the foot-insole interface for load sharing and provide extra support to the heel and arch to reinforce flexibility and stiffness of footwear.

The above embodiments are described by way of example only. Many variations are possible without departing from the scope of the embodiments of the invention as defined in the appended claims. Moreover, aspects and features of the various embodiments described herein can be combined to provide further embodiments.

These and other changes can be made to the embodiments in light of the above-detailed description. In general, in the following claims, the terms used should not be construed to limit the claims to the specific embodiments disclosed in the specification and the claims, but should be construed to include all possible embodiments along with the full scope of equivalents to which such claims are entitled. 

1. An insole assembly comprising: an insole having an upper surface for supporting and contacting an underside of a foot, and at least one protrusion projecting away from the upper surface, wherein at least one protrusion is detachably connected to the insole.
 2. An insole assembly as claimed in claim 1, wherein the one or more protrusions comprises a projecting part which projects from the surface and a connecting part which extends away from the projecting part and into the insole.
 3. An insole assembly as claimed in claim 2, wherein the projecting part of one or more protrusions comprises a first part and a second part and wherein the first part has a different rigidity from the second part.
 4. An insole assembly as claimed in claim 3, wherein the second part at least partially surrounds the first part.
 5. An insole assembly as claimed in claim 4, wherein the second part is relatively less rigid than the first part.
 6. An insole assembly as claimed in claim 1, wherein one or more protrusions comprises a compressible material.
 7. An insole assembly as claimed in claim 1, wherein one or more protrusions comprises an elastomeric material.
 8. An insole assembly as claimed in claim 1, wherein one or more protrusions comprises silicone material.
 9. An insole assembly as claimed in claim 1, wherein one or more protrusions are detachably connected to the insole by a friction fit.
 10. An insole assembly as claimed in claim 1, wherein one or more protrusions are detachably connected to the insole by a threaded connection.
 11. An insole assembly as claimed in claim 1, comprising more than one protrusion and wherein at least two protrusions are different sizes.
 12. An insole assembly as claimed in claim 1, comprising more than one protrusion and wherein at least two protrusions are different shapes.
 13. An insole assembly as claimed in claim 2, comprising more than one protrusion and wherein the connecting part of two or more protrusions are substantially the same.
 14. An insole assembly as claimed in claim 1, wherein the insole comprises a first layer and a second layer, wherein the first layer comprises the surface upon which an underside of a foot may be supported and wherein the one or more protrusions is detachably connected to the second layer and extends through the first layer.
 15. An insole assembly as claimed in claim 14, wherein the first layer comprises one or more apertures and wherein one or more protrusions each extend through a corresponding aperture.
 16. An insole assembly as claimed in claim 15, further comprising an arch support arranged between the first layer and the second layer.
 17. An insole assembly as claimed in claim 16, wherein the arch support is made from composite material.
 18. An insole assembly as claimed in claim 1, wherein one or more protrusions are arranged to project from the surface at or around a heel contacting portion of the surface.
 19. An insole assembly as claimed in claim 1, wherein one or more protrusions are arranged to project from the surface at or around a metatarsal head contacting portion of the surface.
 20. An insole assembly as claimed in claim 1, further comprising a shock absorbing material at or around a heel contacting portion of the surface.
 21. An insole assembly as claimed in claim 1, further comprising a shock absorbing material at or around a metatarsal head contacting portion of the surface.
 22. An insole assembly as claimed in claim 1, wherein at least part of one or more protrusions is frusto-conical in shape.
 23. A sole member comprising an insole assembly of claim 1, a midsole and an outsole.
 24. A footwear item comprising the insole assembly of claim
 1. 25. A method of assembling an insole assembly comprising: providing an insole, selecting one or more protrusions from a group of protrusions of different sizes, and attaching the selected one or more protrusions to the insole.
 26. A method as claimed in claim 25, further comprising: selecting an arch support from a group of arch supports of different rigidities, and incorporating the selected arch support into the insole.
 27. A kit for assembling an insole assembly comprising: an insole having an upper surface for supporting and contacting an underside of a foot, the insole having at least one connecting part for receiving a protrusion, and a plurality of protrusions connectable to respective connecting parts of the insole such that at least one protrusion projects away from the upper surface. 